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E85 Tuning Questions

16GoManGoHC2

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#81
That’s some GREAT and consistent times!! I’d be happy with consistent low 10’s this spring Dyno number wise interested in how much tq you where making to get a judge verses my known tq to gauge what kind of times I could possibly get to on these New 17” 315’s. I’d be happy with a 1.55 60ft and a 135-140 low 10 1/4”. Got to cold here to try out the new gearing combo at the track so guesstimating until spring now lol
 


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#82
I think I have one maybe two more races before I wrap up for the season
 


16GoManGoHC2

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#83
Good luck, May the track Gods be with you!!
 


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#84
That’s some GREAT and consistent times!! I’d be happy with consistent low 10’s this spring Dyno number wise interested in how much tq you where making to get a judge verses my known tq to gauge what kind of times I could possibly get to on these New 17” 315’s. I’d be happy with a 1.55 60ft and a 135-140 low 10 1/4”. Got to cold here to try out the new gearing combo at the track so guesstimating until spring now lol
What happened to the guy who posted "happy as a clam" at 10.73. LOL . Car guys. We're all the same. "Good enough" and "happy with it" last @5min. :LOL:
 


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16GoManGoHC2

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#85
Me? I never said that lol
 


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MaxCarnage

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Thread Starter #86
Does anyone know if you run the flex tune if it will show ethanol percentages all the way from 0%-100%? Ideally I'd like a flex tune for street use, when I run pump gas which has up to 10% ethanol in it, but I also like how it measures ethanol so when I toss in E85 I can watch the percentage go to 85%(ish) then switch to a straight E85 tune for racing. I plan on only using E85 for the track and pump 92 (what I have locally) for street. Just curious how low ethanol will read with HP Tuners.

Also anyone know how accurate the reading is on HP Tuners? Have you also used a tester to see how closely the tester is to what the HP Tuners says it is? I've heard a few people say those testers can read a few percent higher than what the E content really is.
 


hellno

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#87
Does anyone know if you run the flex tune if it will show ethanol percentages all the way from 0%-100%? Ideally I'd like a flex tune for street use, when I run pump gas which has up to 10% ethanol in it, but I also like how it measures ethanol so when I toss in E85 I can watch the percentage go to 85%(ish) then switch to a straight E85 tune for racing. I plan on only using E85 for the track and pump 92 (what I have locally) for street. Just curious how low ethanol will read with HP Tuners.

Also anyone know how accurate the reading is on HP Tuners? Have you also used a tester to see how closely the tester is to what the HP Tuners says it is? I've heard a few people say those testers can read a few percent higher than what the E content really is.
I believe curt told me within 10to 15 percent accuracy I just make sure mine reads 80% before I switch to e85 race tune curt said 75 % minimum , before I last switch to my race tune mine read 82%
 


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#88
Good runs! How much timing were you running?
 


hellno

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#89
Mines runs up to 21 to 22 degrees
 


AlleyCat

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#90
I tried 23. It runs best at 21. Thanks for sharing.
 


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MaxCarnage

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Thread Starter #91
I believe curt told me within 10to 15 percent accuracy I just make sure mine reads 80% before I switch to e85 race tune curt said 75 % minimum , before I last switch to my race tune mine read 82%
Well I was more asking how low will it read Ethanol? So if you run pure pump fuel (which is what I want to do on the flex tune for my street driving). My local pump fuel has anywhere between 2%-10% ethanol in it. Just curious if it will even measure Ethanol content levels that low or not. Mostly I also want the flex tune so that I can do the same you are doing. Run any mix of pump/E, and then when you want to race you just wait until it reads 85% E or so then swap to the E85 tune.

For example what fuel do you run in it during normal street driving? Pure pump gas or a flex mix? If so what's the lowest content percentage you've seen the gauge read?

Since I don't have easy access to Ethanol, I want to save E85 for racing only (Using pump 92 for street on flex tune). After racing, I'll just toss it in the flex tune tune and burn off the remaining E85 with possible pump fuel mix.
 


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Thread Starter #92
Something I'll likely need to ask a tuner before I make the switch to E85 is:

1. On a Redeye what pullies can you swap to before needing either baps or swapping to a different fuel pump system (Assuming you already have FIC1200/ID1300s)? I've read you'll be at about 80% duty cycle on stock pumps (with upgraded injectors). So I don't know how far you should safely push the fuel system, before more flow is needed. So far it sounds like maybe a litens 3.17 or a maybe a 10% lower, and then after that extra pump flow is needed.

2. How far can you push boost on pump fuel until you just need to run E85 100% of the time?

@curt_dusterhofftuning what do you generally charge for a re-tune if needed (depend on mods?)? Lets say for something like just a pulley change? Any updates on more Redeye flex remote tuning? You doing that as of yet?

Trying not to overthink all of this, but I'm also trying to buy what I need the first time, lol.

Thanks for the help guys!
 


hellno

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#93
I haven’t had mine all the way down to 93 yet since I switched to the ethanol I had a minimum of say 95 and it read 27% but I’m sure curt can answer all your questions and when your ready you can believe in his ability and knowledge to get it done , I have 100 percent faith in everything curt has done on my car the proof is in the pudding as they say , he must be good to be able to put up with me because I change my mind all the time lol
 


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Thread Starter #94
I haven’t had mine all the way down to 93 yet since I switched to the ethanol I had a minimum of say 95 and it read 27% but I’m sure curt can answer all your questions and when your ready you can believe in his ability and knowledge to get it done , I have 100 percent faith in everything curt has done on my car the proof is in the pudding as they say , he must be good to be able to put up with me because I change my mind all the time lol
Lol, yeah I'm trying to make up my mind on the direction I plan on going. So far E85 is what I really want, and to run 9s in great DA. Just waiting for the remote tune on Redeye's for flex and my lady to give me the go ahead lol. Between now and then new products likely will pop up to give me more options anyway, lol. The biggest thing is I don't want to take away from the drive-ability of this car, with the exception of winter when it's stored. So hopefully Curt won't fall off the planet between now and when I need a tune from him, haha!
 


hellno

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#95
That’s the amazing thing Is no drivability is suffered I put my factory wheels back on and drive it just like a regular every day car it’s that nice
 


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#96
That’s some GREAT and consistent times!! I’d be happy with consistent low 10’s this spring Dyno number wise interested in how much tq you where making to get a judge verses my known tq to gauge what kind of times I could possibly get to on these New 17” 315’s. I’d be happy with a 1.55 60ft and a 135-140 low 10 1/4”. Got to cold here to try out the new gearing combo at the track so guesstimating until spring now lol
This will be tough in a 6 speed car. My buddy Chad did just about everything to his 6 speed and I think his best ever was a 10.1 at like 143MPH (something like that). You'll find you hit a point where you have all the power you need but can't get it to the ground effectively. Chad hit that point a couple weeks back and is now in selling the 6 speed and getting an auto. Another friend went to the track with us last weekend and at the end of the day he's now decided to also sell the 6 speed and get an auto. I think watching us auto guys make minimal changes and run 9s was a bit demoralizing as well.

Probably not what you wanna hear, but I've personally been there done that and it seems most folks end up at the same place eventually. I'd say consistent mid 10s are doable in a 6 speed though. Would love to see you prove me wrong though so best of luck with the car.
 


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#97
2. Some people go e85 only because they want to run more boost than is safe on pump gas. Also, the flex-fuel tuning is great but it's only accurate to about 10%. As a result, I have to play it a little safe on the tune. What this means is, typically an e85 only tune will perform slightly better at the track. Most would never know the difference but for someone doing a lot of racing, it's worth doing a straight e85 tune.
I am interpreting this as there is no ability for a native flex fuel sensor to be integrated into the factory OS, and because of this stoich is kept conservative and the fuel trims (+/-30%) are used to compensate for the Comd EQ due to irregularities in pump E85. Correct?
 


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#98
Something I'll likely need to ask a tuner before I make the switch to E85 is:

1. On a Redeye what pullies can you swap to before needing either baps or swapping to a different fuel pump system (Assuming you already have FIC1200/ID1300s)? I've read you'll be at about 80% duty cycle on stock pumps (with upgraded injectors). So I don't know how far you should safely push the fuel system, before more flow is needed. So far it sounds like maybe a litens 3.17 or a maybe a 10% lower, and then after that extra pump flow is needed.

2. How far can you push boost on pump fuel until you just need to run E85 100% of the time?

@curt_dusterhofftuning what do you generally charge for a re-tune if needed (depend on mods?)? Lets say for something like just a pulley change? Any updates on more Redeye flex remote tuning? You doing that as of yet?

Trying not to overthink all of this, but I'm also trying to buy what I need the first time, lol.

Thanks for the help guys!
If it's just a pulley change $150. Otherwise kind of depends on changes

I've done one redeye flex. Went well. Would like to do another to confirm although I'm pretty confident in it at this point.
 


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This will be tough in a 6 speed car. My buddy Chad did just about everything to his 6 speed and I think his best ever was a 10.1 at like 143MPH (something like that). You'll find you hit a point where you have all the power you need but can't get it to the ground effectively. Chad hit that point a couple weeks back and is now in selling the 6 speed and getting an auto. Another friend went to the track with us last weekend and at the end of the day he's now decided to also sell the 6 speed and get an auto. I think watching us auto guys make minimal changes and run 9s was a bit demoralizing as well.

Probably not what you wanna hear, but I've personally been there done that and it seems most folks end up at the same place eventually. I'd say consistent mid 10s are doable in a 6 speed though. Would love to see you prove me wrong though so best of luck with the car.
Yeah, if ultimate ETs are your goal and you want to avoid the struggle/commitment - definitely don't use an M6 car. 10.99 is my ambitous goal.
 


16GoManGoHC2

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This will be tough in a 6 speed car. My buddy Chad did just about everything to his 6 speed and I think his best ever was a 10.1 at like 143MPH (something like that). You'll find you hit a point where you have all the power you need but can't get it to the ground effectively. Chad hit that point a couple weeks back and is now in selling the 6 speed and getting an auto. Another friend went to the track with us last weekend and at the end of the day he's now decided to also sell the 6 speed and get an auto. I think watching us auto guys make minimal changes and run 9s was a bit demoralizing as well.

Probably not what you wanna hear, but I've personally been there done that and it seems most folks end up at the same place eventually. I'd say consistent mid 10s are doable in a 6 speed though. Would love to see you prove me wrong though so best of luck with the car.
I unfortunately know and agree with you on this. Trust me, at the track I envy the auto guys, it’s so much easier for so many reasons and couple to that the ability to tweak the transmission and engine to match conditions Etc I guess that’s why at some tracks they separate the manuals from the autos for certain events. If I didn’t have as much time and parts already into mine and getting crap for a trade in on a Redeye the thought of converting has crossed my mind for a few reasons. But I’m pretty thick headed lol and I know I’m up for at least another summer of battling with what I have. I LOVE her on the street because she’s a manual , if I could just have some automatic control over the throttle or power % even by just speed alone it would help me to love her more at the track too :)
 




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